Where do we find out about the 613 mitzvos?

· Sefer HaMitzvos of the Rambam (12th century). This work follows the order of his Mishneh Torah (Yad Chazakah) and lists positive and negative commandments separately.

· Sefer HaChinuch, an anonymous work popularly attributed to one of two scholars named Rav Aharon HaLevi of Barcelona (13th century). This work follows the Rambam’s list of mitzvos, but organizes them by parsha. Depending on the edition of the Chinuch being consulted, the mitzvos may then be organized by positive and negative mitzvos within a given parsha, or in strict chronological order.

· Sefer HaMitzvos HaKatzar, the “abbreviated” book of mitzvos, is a work by R. Yisroel Meir Kagan, the Chofetz Chaim (20th century). This book trims the Sefer HaMitzvos to 77 positive and 194 negative mitzvos that can be observed today. (Additionally, there are 26 mitzvos that can be observed in Israel, but that was not relevant when the Chofetz Chaim collected this work.)

There are other works known as Sefer HaMitzvos, though the Rambam’s is considered the “default.” Others include that of Rav Saadiah Gaon (which actually predates the Rambam’s), Sefer haMitzvos HaGadol (“SMaG”) and Sefer HaMitzvos HaKatan (“SMak”). The commentary of Nachmanides on the Rambam’s work is also invaluable.